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Transcript
Learning:
Classical Conditioning
Associative Learning
Classical conditioning – An
INVOLUNTARY behavior is determined by
what PRECEDES it
Operant conditioning – rewards and
punishment; A VOLUNTARY behavior is
determined by the anticipation of
something that FOLLOWS it.
Which is which?
1. A child is attacked by
a dog. The child
now fears all dogs.
2. You do your
homework every
night to get good
grades and avoid
getting in trouble
from your teachers
and parents.
Classical – involuntary, stimulus
precedes behavior
Operant – voluntary, stimulus
follows behavior
Ivan Pavlov’s
Experiments
Unbeknownst to
most students of
psychology,
Pavlov’s first
experiment was
to ring a bell and
cause his dog to
attack Freud’s
cat.
It’s time for an in-class
experiment!
The Lemonade Powder
Experiment
Ivan Pavlov’s Experiments
Pavlov paired a
neutral stimulus (a
bell) with a meat
powder (which
made the dog
salivate).
Eventually, dog
salivates to bell
alone
The Experimental Design
Identifying Parts
Neutral Stimulus – a stimulus that does not initially elicity
any part of the unconditioned response
Bell
Unconditioned Stimulus (UCS)
Meat powder
Unconditioned Response (UCR)
Salivation
Conditioned Stimulus (CS)
Bell
Conditioned Response (CR)
Salivation
* Hint: replace “conditioned” with “learned” to make it more
intuitive.
Little Albert
John Watson – famous
behavioralist
Little Albert – 11 month old
orphan
Showed him a white rat. No
fear.
Made a loud noise. Albert
cried.
Showed him a white rat and
made a loud noise. Albert
cried. Repeated several times.
Eventually Albert cried at
white rat alone.
Identify the parts
Unconditioned Stimulus (UCS)
Loud noise
Unconditioned Response (UCR)
Fear/crying
Conditioned Stimulus (CS)
White rat
Conditioned Response (CR)
Fear/crying
Watson’s Views
“ Give me a dozen healthy infants, well-formed,
and my own specified world to bring them up
and I’ll guarantee to take any one at random and
train him to become any type of specialist I
might select—doctor, lawyer, merchant-chief,
and yes, even beggar-man and thief, regardless
of his talents, penchants, tendencies, abilities,
vocations, and race of his ancestors. I am going
beyond my facts and I admit it, but so have the
advocates for the contrary and they have been
doing it for many thousands of years.” (1930)
Definitions
Acquisition – initial learning of the stimulus-response
relationship (learning that bell means meat powder)
Extinction – diminished response to the conditioned
stimulus when it is no longer coupled with UCS. (stop
giving meat powder with bell and dog will stop salivating
to bell)
Spontaneous recovery – reappearance of an
extinguished CR after a rest.
Generalization – the tendency to respond to any stimuli
similar to the CS (Dog salivates to other noises)
Discrimination – the ability to distinguish between the CS
and similar stimuli (Dog only salivates to specific tone)
Application to Little Albert
If Little Albert generalized, what would we expect to happen?
– He might cry at the sight of similar objects (he did – rabbit, dog, sealskin
coat, some rumors – Santa’s beard)
How could we teach Little Albert to discriminate?
– Continually expose him to stimuli similar to the rat, but only make the
loud noise when exposing him to the rat
How could Little Albert’s conditioning be extinguished?
– Continually expose him to a white rat without making the loud noise
(unfortunately, this was never done because Little Albert was adopted
soon after the original experiments (he would be 83 now if he is still
alive – probably scared of rats!)
If Little Albert is still alive, his fear of white rats is likely to have
been extinguished (no loud noise when he sees a rat).
However, occasionally, when he sees a rat, he may find that his
heart races for a second or two. What is this called?
– Spontaneous recovery
Cognitive Processes
It was once thought that
cognitive processes
weren’t involved in
classical conditioning.
Now we know better. For
example, therapists give
alcoholics drink
containing a nauseaproducing drug to
condition them to avoid
alcohol. Because clients
KNOW that the drug is
what is actually causing
the nausea, it doesn’t
work so well.
Biological Predispositions
It was once believed that conditioning occurred the same in all animals
(and therefore you could study human behavior by studying any
animal) and that you could associate any neutral stimulus with a
response. Not so. Animals have biological predispositions to
associating certain stimuli over others
Example – You eat a novel food and later get sick. You will be
conditioned to associate the taste of the FOOD with getting sick
(and thus avoid that food in the future), but NOT the music playing in
the restaurant, the plate it was served on, or the perfume your
neighbor was wearing.
It is much easier to condition someone to have a fear of snake than
of flowers.
Birds hunt by sight and will more quickly become conditioned to the
SIGHT of tainted food
Cancer patients and
chemotherapy.
Cancer patients tend to
associate the nausea
produced by
chemotherapy with the
hospital setting.
– UCS
chemotherapy
– UCR
nausea
– CS
hospital
– CR
nausea
Taste Aversion Questionnaire
1 - - - - - 2 - - - - - 3 - - - - - 4 - - - - - 5 - - - - - 6 - - - - 7 - - - - - 8 - - - - - 9 - - - - - 10
Dislike extremely
Neutral
Like extremely
Imagine a bowl of your favorite soup, one
that would be a perfect 10.
Now imagine that the soup was served to you in
an ordinary bowl, but had been stirred by a
thoroughly washed, used flyswatter. How much
would you like to eat the soup?
If that flyswatter were brand new, how much
would you like to eat the soup?
Taste Aversion Questionnaire
1 - - - - - 2 - - - - - 3 - - - - - 4 - - - - - 5 - - - - - 6 - - - - 7 - - - - - 8 - - - - - 9 - - - - - 10
Dislike extremely
Neutral
Like extremely
If the soup was first stirred with a thoroughly
washed but used comb, how much would you
like to eat it?
If the soup was served in a thoroughly washed,
used dog bowl, how much would you like to eat
it?
Taste Aversion Questionnaire
1 - - - - - 2 - - - - - 3 - - - - - 4 - - - - - 5 - - - - - 6 - - - - 7 - - - - - 8 - - - - - 9 - - - - - 10
Dislike extremely
Neutral
Like extremely
Now fantasize about your favorite cookie,
again one that would rate a perfect 10.
How much would you like to eat this cookie if
you’d dropped it on the grass first?
How much would you like to eat it if a waiter had
taken a bite first? An acquaintance? A good
friend?
Taste Aversion Questionnaire
1 - - - - - 2 - - - - - 3 - - - - - 4 - - - - - 5 - - - - - 6 - - - - 7 - - - - - 8 - - - - - 9 - - - - - 10
Dislike extremely
Neutral
Like extremely
If the soup was first stirred with a thoroughly
washed but used comb, how much would you
like to eat it?
If the soup was served in a thoroughly washed,
used dog bowl, how much would you like to eat
it?